Physicians who have completed a residency and perhaps a fellowship are usually superb clinicians, but generally are not well prepared to meet the research requirements of a career in academic medicine. This proposal describes a plan for a Research Career Development Program in men's reproductive health for pediatricians, internists, endocrinologists and/or urologists at the University of Washington. The major goal of this program is to provide the research training to enable young physicians to establish research careers and eventually become independent investigators. The principal training format proposed is a mentored experience with a successful investigator (clinical, translational or basic) for two to five years. During this time, each of the two scholars will devote most of his/he time to research projects, whereby he/she acquires the knowledge and skills to become independent and assume a faculty position. In addition, in the initial years of each scholar's research training, formal coursework will be provided, as appropriate for the scholar's interests. This proposed UW Male Reproductive Health Research Program has twelve mentors with extensive research experience and funding that collectively represent both strong clinical and basic science expertise in subject areas that directly relate to men's reproductive health. This is a multidisciplinary proposal in that the mentors have their primary expertise and appointments in the Departments of Medicine, Urology, Epidemiology, Pharmacology, Physiology and Biophysics and Obstetrics and Gynecology. Each proposed mentor has a record of excellence in research and documented experience in training young investigators. The Departments of Medicine and Urology will diligently recruit outside scholars, and they have a relatively large pool of residents, fellows, and junior faculty eager to compete for the two proposed scholar awards. The Medicine and Urology departments and the School of Medicine at the University of Washington are prepared to make major commitments of resources and funding to support this proposed research center. In many ways, the University of Washington is the ideal location for a career development program in male reproductive health. The University has a wealth of resources and experience in male reproductive research, and can provide many opportunities for scholars to embark on successful research careers, which will serve to foster new therapeutic breakthroughs in issues relevant to male reproductive health.